That's a good question. I haven't seen any of them at the 3 Apple Store's in my area. I'm going to say you can't get them in store, only online? Seeing how Apple Store's only carry stock options. You could always call them and see what's up.

In theory you can only get the keyboard with #-pad, when ordering via online Apple Store, but some Apple Stores or premium resellers can use discretion and exchange the original keyboard with a #-pad one without additional charge.
So ask your local store, or order online.

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